Friction-gear for cars.



T. H. SYMINGTON.

FRICTION GEAR FOR CARS.

APPLICATION TILED AUG. 23, 1910.

Patented Sept. 26, 1911.

' [IVVEIVTOR Toaflwhomitmayconcem:

THOIARH. BYHINGION, F BALTIMORE, MARYLAND.

' FRICTION-GEAR FOB CABS.

. specification -m mur. Patented Sept. 26, 1911.

Application filed August 38, 1810. Berlal ll'o. 578,594.

Be it known that I, Tnoms H. Snp vo- 1011, a citizen of the Umt'ed States, residing at Baltimore city and State of Maryland, have invented certain new and useful Imand frictional hereinafter set forth and provements in Friction-Gears for Cars, of which the follo is a specification.

My invention r lates to draft and gear for cars, and especially to cushioning elements forming parts thereof for transforming the momentum of the car and its load or of an adjacent car or cars in a train into the work of compressing a spring or springs and movingrmetalhc elements with their surfaces in ictional contact one relative to the other, whereby the greater part of the kinetic energy 18 not transmitted to the. draft members or sills and to the floor frame of the car.

The main object of my invention is the provision of a combined spring and fr ctional device which will permit an'imtial compression of one of the springs before the other spring and the friction elements are brought into effective action, and m which a positive separation of the frictional elements, or a positive release of the same shall be effected by the recoil or expansion of one of the spr' gs when it has been compressed in drawing or buifing.

' y invention consists in certain novelties of construction and combinations of parts claimed.

The accompanying drawing illustrates an example of the physical embodiment of the invention constructed and arranged accordg to the best mode of procedure I have so far devised for the purpose.

Figure 1 is a top plan view of a gear comprisin a draw bar, followers,-keys, and links, an with my improved spring and frictional device interposed bet-ween the followers. Fi 2 is a lon 'tudinal vertical section of the iction an spring device on an enlarged scale. Fig. 3 is a hal end elevation and a half cross sectional view taken on line B--B of Fig. 1. Fig. 4 is a view in' rspective of one of the friction blocks. ig. 5 is an end elevation .view of Fig. 4. Figs.

6 and 7 are side andends views of the friction wedge.

In Fig. 1. the numeral 1 designates a slotted draw bar; 2, a filler block 3', slotted followers; 4, slotted channel beam; 5, slotted links; 6, keys assed throu h the draw -bar, followers, iinks, and c annel and in the beams, and 7 is my imtpro ved spring and friction device inter in operative position between the 0 owers.

tivel large coiled sma coiled sprin and five friction bl construction. The

spring 9, a relatively 10, a friction wedge 11, ocks 12 each of identical casing 8 is shown of a hollow cylindrical shape open at one end and provided with an inwardly extended flange 13 at the opposite end, but the casmg may in practice be of a different shape in cross section.

The relatively large s ring 9 is located within the casing with t evcoil at one end abuttin the flange 13 of the casing. The relativ y small spring 10 is of substantially the same length as the larger spring in this example and located inside the larger spring with one end in line with the opening in the casing bounded b the flange 13, the diameter of the spring being less than the diameter of the opening so the end of the spring can bear against the follower block at the end of the casing when the larger spring is compressed.

The device 7 comprises a casing 8, a rela- The friction wedge 11 has an extension or centering lug 14 at one end located within one end of the smaller 3 ring, a plain surface 15 against which t e end coil of the smaller splring abuts, and the opposite end is of-the s ape of a five faced pyramid, each face 16 being of a'trian-gular shape and constituting a frictional surface. Intermediate-the ends the wedge is of a pentagonal shape'in cross section providing five rectangular surfaces 17 in planes parallel with the axis of the wedge.

Each friction block 12 has a convex frictional surface 18 in frictional contact with the inner surface of the casing, an inclined triangular shaped frictional surface- 19 in frictional contact with a frictional surface 16 of the wedge, a plain rectangular surface 20 matchin a rectangular surface 17 of the wedge, an an end ,wall 21 adapted to enga e'a follower.

, The wed cast hollow or cored in casting, as shown, or otherwise to reduce the weights of the same, case of a friction block 12 shown an opening 22 is provided bounded by a curved surface 23, which surface in connection with the like surfaces of the other blocks when assembled forms a bearing for the reception'of a centering lug 24 on the face of ge and friction blocks may be I a follower, shown by dotted lines, Fig. 1; in other words, a cylindrical recess is present in the vertical face of the assembled blocks to receive the centering lug on a followei'zf The. centering lug 25 of the rear follower A may be located within the end of the smaller spring and the opening bounded by the flange 13 of the casing, as shown. I

, When assembled, the parts'and elements of the device normally positions shown ,by Flg. 2, the ends of the friction blocks'projectinga suitable distance beyond the open end of the casing, the smaller spring being fully'expanded, and

the larger spring slightly under compress1on.

The mode of operation is as follows: In bufling, the front follower moves rearwardly, forcing the friction blocks into the casing and compressing the larger spring, for example, one-half of an vinch, and absorbing or cushioning the lighter shocks.

' At the same time the friction wedge and their curved surfaces frictionally engage the interior curved surface of the casing,

and at the same time the triangular surfaces 19 of the blocks move over the triangular surfaces of the wedge. When pressure is removed from the draw bar the larger sprin by expansive energy moves thefriction blocks outwardly and effects a positive release, so the blocks and wedge do not bind or remain wedged together, which is a common occurrence 1n many types of friction gear heretofore designed. The wedge and smaller spring simultaneously assume the positions substantially as shown in Fig. 2 when the friction blocks are moved outwardly in the act of release. In drawing the mode of operation is substantially the same, however, as is obvious, the friction blocks are stationary, bearing against the front follower and the casing moves forwardly relative to them.

To increase or diminish the frictional resistance the angles of the frictional engaging surfaces of the wedge and the blocks relative to the axis of the wedge may be changed as the particular service may reu1re.

While I have illustrated and specifically described only one example of the embodiment of the invention, the same may be embodied otherwise with the shapes and di- 'mensions of the several elements changed and the disposition of parts altered without constituting substantial departures.

occupy the relative U on a further rearward travel What I claim is: 1. A combined spring and friction device comprising a metallic casing; two springs concentrically disposed within the casing; a plurality of friction blocks arranged within the casing with their outer surfaces in frictional contact with the inner surface of the casing and their ends bearing against the outer spring only so the blocks may compress and be moved by said spring, each ofsaid blocks having an inclined friction surface; and a wedge with its head in engagement with the end of the inner spring and its surface oblique to the axis of the wedge in frictional contact with the inclined friction surfaces of the friction blocks, and so the inner spring will force the oblique outer surface of the wedge against the inclined surfaces of the blocks.

2. A combined spring and friction device comprising a metallic casing; two s rings concentrically disposed within the casing; a plurality of friction blocks arranged within the casing with their outer surfaces in frictional contact with the inner surface of the casing'and their ends bearing against the outer spring, each of said blocks having an inclined friction surface; and a wedge with its head in engagement with the end of the inner spring and its surface oblique tothe axis of the wedge in frictional contact with the inclined friction surfaces of the friction blocks; the saidcasing having an opening at the end of greater diameter than the diameter of the inner spring, whereby when the device is combined with front and rear the inner spring is substantially compressed.

3. A combined spring and friction device comprising a metallic casing; two springs concentrically disposed within the casing; a plurality of friction blocks arranged within .the casing with their outer surfaces in frictional contact with the inner surface of the casing and their ends bearing against the outer spring, each of said blocks having an inclined friction surface; and a wedge with its headin engagement with the'end of the inner spring and its surface oblique to the axis of the wedge in frictional contact with the inclined frictional surfaces of the friction blocks; the said friction blocks arranged concentrically within the casing having at their projecting ends a recess to receive the stem of a follower.

4, Aicombined spr' g and friction device comprising a. metalli casing; two springs concentrically disposed within the casing; a plurality of friction blocks arranged within the casing with their outer surfaces in frictional contact with the inner surface of the casing and their ends bearing against the outer spring, each of said blocks having an inclined friction surface; and-a wedge pro vided with a plurality of plain surfaces 05- In testimony whereof I aflix my signature lique to the axis of said wedge, having its in presence of two witnesses.

head in engagement with the end of the inner spring only and its said plain' oblique THOMAS SYMINGTON' 5 surfaces in frictional contact with the m- Witnesses:

clined friction surfaces of the friction HENRY H. DINNEEN,

blocks. S. L. RoMPs. 

